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  <script>
    const arr = [8, 2, 6, 5, 4, 1, 3]
    const num = 7
    const arr2 = []
   for (let i = 0; i < arr.length; i++) {
    for (let j = 0; j < arr.length; j++) {
      if(arr[i]+arr[j] === num){
        arr2.push(arr[i],arr[j])
      }
      
    }
   }
   console.log(arr2)
   
  </script>
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